Synonyms for

Efficacy

Verb / ˈefɪˌkæsi: / Another word for efficacy — explore alternatives below. For syllable breakdowns and pronunciation, see this word on Syllablesworld.

Definition

the ability to produce a desired or intended result

Synonyms & similar words

efficaciousness inefficacy effectiveness potency success productivity efficiency usefulness performance capability proficiency validity clout power strength impact influence punch force puissance virtue benefit

Synonyms by register

Formal

effectiveness potency efficacy capability power

Informal

effectiveness works gets the job done

Literary

virtue force might

Antonyms

ineffectiveness impotence futility uselessness failure inadequacy

Common collocations

  • clinical efficacy
  • therapeutic efficacy
  • demonstrate efficacy
  • efficacy of the treatment
  • efficacy rate
  • efficacy study
  • efficacy data

Word family

noun efficacy
adjective efficacious

Usage note

Efficacy refers to the ability to produce a desired or intended result, often used in scientific or medical contexts. It is distinct from 'effectiveness,' which refers to the degree to which something is successful in producing a desired result in practice.

Example sentences

  1. The efficacy of the new cleaning product was impressive.
  2. The efficacy of the vaccine was proven by its ability to prevent the spread of the disease.
  3. The efficacy of the workout plan was evident in the athlete's improved performance.
  4. The efficacy of the teacher's lesson plan was demonstrated by the students' high test scores.
  5. The efficacy of the new security measures was evident in the decrease of thefts.

Quotes

  • The ultimate measure of the efficacy of any written work is its ability to be understood by the average reader.
  • The efficacy of prayer is not based on whether we get what we want, but on whether we become the person we need to be.
  • The efficacy of a politician is not in what they say, but in what they do.

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